Many modern weapon systems, particularly missile systems, include a variety of electronic components that require electrical power to function. These weapon systems face the problem of being able to deliver electrical power to their electronic systems after long periods of non-use, such as when the weapons are stockpiled. Many power sources, such as conventional batteries, tend to deteriorate over time and in extreme temperatures, making them unsuitable in weapons that must be stored for long periods and/or in hostile climate conditions. Consequently, many weapon systems rely on thermal batteries, which engage chemical reactions to generate electrical power upon activation. Since thermal batteries are not activated until they receive an external electrical impulse, they have a much longer shelf-life than other batteries, making them ideal in weapon systems that must be stored for long periods.
However, reliably generating the external electrical impulse to initiate a thermal battery is problematic. Initiating the thermal battery using conventional batteries faces the same battery-life issues discussed above, making them an unreliable source for the thermal battery initiation charge after being stored for long periods. Additionally, conventional batteries and other initiator mechanisms may be difficult to replace due to, for example, the design of certain weapon systems and logistical issues arising under wartime conditions. Conventional initiator mechanisms have the additional disadvantage that they may be accidentally triggered during shipping or field-handling operations, prematurely activating the thermal battery and neutralizing the capability of the weapon.